Choosing the Right Silane Adhesion Promoters for SMP Sealants

SpecialChem
/
Aug 21, 2002

Silane-modified polypropylene oxides (SMPs), or MS Polymers, offer a wide range of physical properties and can be formulated into a variety of moisture-curable adhesives and sealants. Silane additives greatly influence the performance of SMP adhesives and sealants and play a key role in the success of these products.
This article outlines silane chemistry and the preparation and characterization of a low-modulus SMP sealant. The article also reviews the impact of various aminosilane adhesion promoters on the sealant's shelf life, cure rate, physical properties, and dry and wet adhesion.
Oligomeric diaminosilanes, such as DYNASYLAN 1146 silane, offer multifunctionality, a low volatility and a reduced amount of volatile organic compounds (VOCs) to the formulator. An increase in elongation and a decrease in modulus of the SMP sealant are realized. Primerless adhesion generated by DYNASYLAN 1146 silane outperforms commonly used monomeric aminosilanes due to better wetting/film formation.
Construction sealants based on SMPs have been used successfully in Japan for several decades.